Detecting when PopupApplet is iconified

[Aaron J. Seigo]

(more in reply to Sebastian's email, but Rob's reply is very illuminating as 
to the issues :)

On March 19, 2010, Rob Hasselbaum wrote:
> It's expensive. So just blocking the updates from propagating between
> the data engine and the applet isn't enough.

if nothing it connected to a source and the source was created using 
sourceRequestEvent() it is automatically removed.

> And a nice benefit of
> pausing the data engine's work is that the applet becomes idle on its
> own.

* dataengines are inherently shared between visualizations (that's actually 
kind of the entire point of them); so this won't work if one visualization 
(applet, e.g.) is shown and the other isn't

* this would create a nasty set of circular dependencies in various conditions 
where the DataEngine is supposed to push updates to the Applet, but now the 
Applet is saying not to do that for the time being. who is in control?

this is why there is disconnectSource and sourceRequestEvent. use them 
properly, just as the API encourages one to, and everything Just Works(tm)

-- 
Aaron J. Seigo
humru othro a kohnu se
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